/**
* @brief Initializes the GPIOx peripheral according to the specified
* parameters in the GPIO_InitStruct.
��ʼ��GPIOx ����ͨ������GPIOx(����mode\speed\PuPd\otype)
* @param GPIOx: where x can be (A, B, C, D, E or H) to select the GPIO peripheral.
���� GPIOx(A, B, C, D, E or H)
* @param GPIO_InitStruct: pointer to a GPIO_InitTypeDef structure that
* contains the configuration information for the specified GPIO
* peripheral.
* GPIO_Pin: selects the pin to be configured: GPIO_Pin_0 -> GPIO_Pin_15
* GPIO_Mode: selects the mode of the pin:
* - Input mode: GPIO_Mode_IN
* - Output mode: GPIO_Mode_OUT
* - Alternate Function mode: GPIO_Mode_AF
* - Analog mode: GPIO_Mode_AN
* GPIO_Speed: selects the speed of the pin if configured in Output:
* - Very Low: GPIO_Speed_400KHz
* - Low: GPIO_Speed_2MHz
* - Medium: GPIO_Speed_10MHz
* - High: GPIO_Speed_40MHz
* GPIO_OType: selects the Output type (if the selected mode is output):
* - Push-pull: GPIO_OType_PP
* - Open Drain: GPIO_OType_OD
* GPIO_PuPd: configures the Pull-up/Pull-down resistor on the pin:
* - pull-up: GPIO_PuPd_UP
* - pull-down: GPIO_PuPd_DOWN
* - Neither pull-up nor Pull-down: GPIO_PuPd_NOPULL
����Ϊ1��GPIO_TypeDef* GPIOx������GPIOx)�������������ļĴ�����
2��GPIO_InitTypeDef* GPIO_InitStruct ������д�û���Ҫ�����͡��ٶȡ����ģʽ�����������ȣ�
* @retval None
*/
void GPIO_Init(GPIO_TypeDef* GPIOx, GPIO_InitTypeDef* GPIO_InitStruct)
{
uint32_t pinpos = 0x00, pos = 0x00 , currentpin = 0x00;
/* Check the parameters */
assert_param(IS_GPIO_ALL_PERIPH(GPIOx));
assert_param(IS_GPIO_PIN(GPIO_InitStruct->GPIO_Pin));
assert_param(IS_GPIO_MODE(GPIO_InitStruct->GPIO_Mode));
assert_param(IS_GPIO_PUPD(GPIO_InitStruct->GPIO_PuPd));
/* -------------------------Configure the port pins---------------- */
/*-- GPIO Mode Configuration --*/
for (pinpos = 0x00; pinpos < 0x10; pinpos++)
{
pos = ((uint32_t)0x01) << pinpos;
/* Get the port pins position */
currentpin = (GPIO_InitStruct->GPIO_Pin) & pos;
if (currentpin == pos)
{
GPIOx->MODER &= ~(GPIO_MODER_MODER0 << (pinpos * 2));/*һ��pinռ2λ����˱����ƶ�pinpos * 2,�����*/
GPIOx->MODER |= (((uint32_t)GPIO_InitStruct->GPIO_Mode) << (pinpos * 2));/*һ��pinռ2λ����˱����ƶ�pinpos * 2,�ٸ�ֵ*/
if ((GPIO_InitStruct->GPIO_Mode == GPIO_Mode_OUT) || (GPIO_InitStruct->GPIO_Mode == GPIO_Mode_AF))
{ /*��ѡ�����ģʽ����AFģʽ,�����ٶȡ�������͡�*/
/* Check Speed mode parameters */
assert_param(IS_GPIO_SPEED(GPIO_InitStruct->GPIO_Speed));
/* Speed mode configuration */
GPIOx->OSPEEDR &= ~(GPIO_OSPEEDER_OSPEEDR0 << (pinpos * 2));/*һ��pinռ2λ����˱����ƶ�pinpos * 2,�����*/
GPIOx->OSPEEDR |= ((uint32_t)(GPIO_InitStruct->GPIO_Speed) << (pinpos * 2));/*һ��pinռ2λ����˱����ƶ�pinpos * 2,�ٸ�ֵ*/
/*Check Output mode parameters */
assert_param(IS_GPIO_OTYPE(GPIO_InitStruct->GPIO_OType));
/* Output mode configuration */
GPIOx->OTYPER &= ~((GPIO_OTYPER_OT_0) << ((uint16_t)pinpos)) ;/*һ��pinռ1λ����˱����ƶ�pinpos ,�����*/
GPIOx->OTYPER |= (uint16_t)(((uint16_t)GPIO_InitStruct->GPIO_OType) << ((uint16_t)pinpos));/*һ��pinռ1λ����˱����ƶ�pinpos ,�ٸ�ֵ*/
}
/*������*/
/* Pull-up Pull down resistor configuration */
GPIOx->PUPDR &= ~(GPIO_PUPDR_PUPDR0 << ((uint16_t)pinpos * 2));/*һ��pinռ2λ����˱����ƶ�pinpos * 2,�����*/
GPIOx->PUPDR |= (((uint32_t)GPIO_InitStruct->GPIO_PuPd) << (pinpos * 2));/*һ��pinռ2λ����˱����ƶ�pinpos*2 ,�ٸ�ֵ*/
}
}
}
void GPIO_Init(GPIO_TypeDef* GPIOx, GPIO_InitTypeDef* GPIO_InitStruct)
{
uint32_t currentmode = 0x00, currentpin = 0x00, pinpos = 0x00, pos = 0x00;
uint32_t tmpreg = 0x00, pinmask = 0x00;
/* Check the parameters */
assert_param(IS_GPIO_ALL_PERIPH(GPIOx));
assert_param(IS_GPIO_MODE(GPIO_InitStruct->GPIO_Mode));
assert_param(IS_GPIO_PIN(GPIO_InitStruct->GPIO_Pin));
/*---------------------------- GPIO Mode Configuration -----------------------*/
currentmode = ((uint32_t)GPIO_InitStruct->GPIO_Mode) & ((uint32_t)0x0F);
if ((((uint32_t)GPIO_InitStruct->GPIO_Mode) & ((uint32_t)0x10)) != 0x00)
{
/* Check the parameters */
assert_param(IS_GPIO_SPEED(GPIO_InitStruct->GPIO_Speed));
/* Output mode */
currentmode |= (uint32_t)GPIO_InitStruct->GPIO_Speed;
}
/*---------------------------- GPIO CRL Configuration ------------------------*/
/* Configure the eight low port pins */
if (((uint32_t)GPIO_InitStruct->GPIO_Pin & ((uint32_t)0x00FF)) != 0x00)
{
tmpreg = GPIOx->CRL;
for (pinpos = 0x00; pinpos < 0x08; pinpos++)
{
pos = ((uint32_t)0x01) << pinpos;
/* Get the port pins position */
currentpin = (GPIO_InitStruct->GPIO_Pin) & pos;
if (currentpin == pos)
{
pos = pinpos << 2;
/* Clear the corresponding low control register bits */
pinmask = ((uint32_t)0x0F) << pos;
tmpreg &= ~pinmask;
/* Write the mode configuration in the corresponding bits */
tmpreg |= (currentmode << pos);
/* Reset the corresponding ODR bit */
if (GPIO_InitStruct->GPIO_Mode == GPIO_Mode_IPD)
{
GPIOx->BRR = (((uint32_t)0x01) << pinpos);
}
else
{
/* Set the corresponding ODR bit */
if (GPIO_InitStruct->GPIO_Mode == GPIO_Mode_IPU)
{
GPIOx->BSRR = (((uint32_t)0x01) << pinpos);
}
}
}
}
GPIOx->CRL = tmpreg;
}
/*---------------------------- GPIO CRH Configuration ------------------------*/
/* Configure the eight high port pins */
if (GPIO_InitStruct->GPIO_Pin > 0x00FF)
{
tmpreg = GPIOx->CRH;
for (pinpos = 0x00; pinpos < 0x08; pinpos++)
{
pos = (((uint32_t)0x01) << (pinpos + 0x08));
/* Get the port pins position */
currentpin = ((GPIO_InitStruct->GPIO_Pin) & pos);
if (currentpin == pos)
{
pos = pinpos << 2;
/* Clear the corresponding high control register bits */
pinmask = ((uint32_t)0x0F) << pos;
tmpreg &= ~pinmask;
/* Write the mode configuration in the corresponding bits */
tmpreg |= (currentmode << pos);
/* Reset the corresponding ODR bit */
if (GPIO_InitStruct->GPIO_Mode == GPIO_Mode_IPD)
{
GPIOx->BRR = (((uint32_t)0x01) << (pinpos + 0x08));
}
/* Set the corresponding ODR bit */
if (GPIO_InitStruct->GPIO_Mode == GPIO_Mode_IPU)
{
GPIOx->BSRR = (((uint32_t)0x01) << (pinpos + 0x08));
}
}
}
GPIOx->CRH = tmpreg;
}
}
